Adaptive steering controller to improve handling stability for driver-combined-vehicles system

If the dynamics of combined vehicles such as tractor-semitrailer varies greatly, it may be very difficult for inexperienced drivers to achieve good handling stability. Moreover, once combined vehicles become unstable, it is very difficult for all drivers to stabilize vehicles. However, if the behavior of actual combined vehicles tracks a designed desired combined vehicle, the good handling property can be maintained even when the dynamics of actual combined vehicles varies large. In this paper, to achieve good handling property even for large variation of vehicle dynamics, a design method for a desired combined vehicle is shown, and then, an adaptive steering controller is developed so that the actual vehicle tracks the desired vehicle. The developed adaptive steering controller has strong robustness for the uncertainties of vehicle parameters. Moreover, a driver model is introduced to show the characteristics of driver. Carrying out numerical simulations, it is shown that the developed adaptive steering controller is very useful for the driver-combined-vehicles system.